Novel benzthiazolylurea derivatives, compositions containing them and their use as herbicides

ABSTRACT

The invention discloses novel herbicidally active and plant growth-regulating benzthiazolylurea derivatives of the formula ##STR1## wherein R 1  is hydrogen, C 1  -C 6  alkyl, C 3  -C 6  alkenyl, C 3  -C 6  -alkylnyl or C 3  -C 6  cycloalkyl; R 2  has the same meaning as R 1  or is C 1  -C 6  alkoxy; R 1  and R 2 , together with the nitrogen atom to which they are attached, also form a 5- to 6-membered heterocyclic ring which can be substituted by C 1  -C 3  alkyl; R 3  is hydrogen, C 1  -C 6  alkyl, an alkali metal cation or an alkaline earth metal cation or a C 1  -C 4  alkylammonium radical, the alkyl moieties of which can be substituted by OH, NH 2 , CN or C 1  -C 4  alkoxy; R 5  to R 9  are preferably hydrogen or C 1  -C 4  alkyl, but can also have one of the other meanings defined more closely in the specification; X 1  and X 2 , each independently of the other, is a C 1  -C 8  alkoxy or C 1  -C 8  alkylthio radical which can be substituted by halogen and/or interrupted by oxygen or sulfur, while X 1  and X 2  together can also be a double bonded oxygen atom or C 2  -C 3  alkylene-dioxide or -disulfide which can be substituted in the alkyl moiety by halogen, C 1  -C 6  alkyl or C 1  -C 6  alkoxy or C 1  -C 4  alkylthio; and Y is an oxygen or a sulfur atom.

The present invention relates to novel benzthiazolylurea derivativeshaving herbicidal and plant growth-inhibiting properties. The inventionalso relates to the production of these compounds, to compositionscontaining them, and to methods of controlling unwanted plant growth,especially in crops of useful plants, which comprises the use thereof.

Benzthiazolylureas of similar structure are known from the literature(cf. for example German Offenlegungsschrift No. 1 932 699 and U.S. Pat.No. 3,682,945). The benzthiazolylurea derivatives of this invention arenew and have excellent herbicidal properties.

The novel benzthiazolylurea derivatives have the formula ##STR2##wherein R₁ is hydrogen, C₁ -C₆ alkyl, C₃ -C₆ alkenyl or C₃ -C₆ alkynylor C₃ -C₆ cycloalkyl,

R₂ has the same meaning as R₁ or is C₁ -C₄ alkoxy,

R₁ and R₂, together with the nitrogen atom to which they are attached,also form a 5- to 6-membered heterocyclic ring which can be substitutedby C₁ -C₃ alkyl,

R₃ is hydrogen, C₁ -C₆ alkyl, C₃ -C₆ alkenyl or C₃ -C₆ alkynyl, or is aradical (1/n) M^(n)⊕, wherein M is an n-valent alkali metal cation oralkaline earth metal cation or an ammonium radical ##STR3## wherein eachof R_(a), R_(b), R_(c) and R_(d) independently is hydrogen, benzyl or C₁-C₄ alkyl which can be substituted by OH, NH₂, CN or C₁ -C₄ alkoxy,

R₄ and R₈, each independently of the other, is hydrogen, halogen, or C₁-C₈ alkyl which is unsubstituted or substituted by halogen orinterrupted by oxygen or sulfur,

R₅ and R₉, each independently of the other, has the same meaning as R₄,and is additionally cyano, phenyl which is unsubstituted or substitutedby halogen, nitro, trifluoromethyl, C₁ -C₄ alkoxy or C₁ -C₄ alkylthio,or is the carboxyl group, a C₁ -C₄ alkoxycarbonyl or C₁ -C₄alkylthiocarbonyl group, the (1/n)M^(n)⊕ carboxyl salt, the carbamoylgroup or a N-(C₁ -C₈ alkyl)carbamoyl group, the alkyl moiety of whichcan be substituted by halogen and/or interrupted by oxygen or sulfur,

R₆ and R₇, each independently of the other, is hydrogen,

C₁ -C₈ alkyl which is unsubstituted or substituted by halogen orinterrupted by oxygen or sulfur; phenyl which is unsubstituted orsubstituted by halogen, nitro, trifluoromethyl, C₁ -C₄ alkoxy or C₁ -C₄alkylthio;

C₃ -C₈ cycloalkyl which is unsubstituted or substituted by halogen, C₁-C₆ alkoxy or C₁ -C₄ alkylthio;

C₃ -C₈ alkenyl or C₃ -C₈ alkynyl, each of which is unsubstituted orsubstituted by halogen or interrupted by oxygen or sulfur;

whilst R₆ and R₇ together can form a C₂ -C₅ alkenylene chain which canbe substituted by halogen, C₁ -C₆ alkyl or

C₁ -C₆ alkoxy or C₁ -C₄ alkylthio;

R₄ and R₆, and R₆ and R₈, together can form a C₁ -C₅ alkylene chainwhich can be substituted by halogen, C₁ -C₆ alkyl or C₁ -C₆ alkoxy or C₁-C₄ alkylthio;

Y is an oxygen or a sulfur atom, and

X₁ and X₂, each independently of the other, is a C₁ -C₈ alkoxy or C₁ -C₈alkylthio radical which can be substituted by halogen and interrupted byoxygen or sulfur, whilst X₁ and X₂ together are a double bonded oxygenatom, C₂ -C₄ alkylenedioxide or -disulfide which can be substituted inthe alkyl moiety by halogen, C₁ -C₆ alkyl or C₁ -C₆ alkoxy, C₁ -C₄alkylthio or halomethyl.

In the above definitions, the alkyl radicals or alkyl moieties of alkoxyor alkylthio radicals contain the indicated number of carbon atoms.However, they are preferably lower radicals which can be unbranched,such as methyl, ethyl, propyl and butyl, or branched, such as isopropyl,sec-butyl, isobutyl and tert-butyl. The preferred alkenyl and alkynylradicals are allyl, methallyl, buten-2-yl, propargyl, methylpropargyland butyn-2-yl. Preferred cycloalkyl radicals are cyclopropyl,cyclopentyl and cyclohexyl. Alkylene chains have preferably 3 to 5 chainmembers so as to form 5- and 6-membered rings with the carbon atoms towhich they are attached. The heterocyclic rings formed by R₁ and R₂ alsohave 5 or 6 ring members and are preferably pyrole, pyrrolidine,pyridine, methylpyridine, piperidine or morpholine.

The novel compounds of the formula I have good herbicidal action againstboth grass weeds and broadleafed weeds, while interesting selectivelyhas been observed in crops of monocots such as maize and cereals, andalso in crops of individual dicots, e.g. soybeans. The novel compoundscan be employed both as postemergence and preemergence herbicides. Ratesof application from 0.1 to 5 kg per hectare are normally required.

A total herbicidal action is achieved if the rate of application issufficiently high. Application can be both pre- and postemergence, andthe rates of application can vary within wide limits, e.g. from 0.1 to10 kg of active ingredient per hectare.

The compounds of formula I also have good growth-regulating action(growth inhibition). In particular, they inhibit plant growth. Thefollowing effects may be cited as examples of the useful application ofthe compounds of the invention:

the reduction of the vegetative growth of soybeans and similarleguminous plants, resulting in an increase in yield of these crops;

the inhibition of unwanted growth of suckers in tobacco plants whoseleading shoots have been cut, thereby promoting the formation of largerand finer leaves;

the inhibition of the growth of grass and dicots such as fruit trees,ornamental trees, bushes and hedgerows, with the aim of reducing cuttingwork;

the inhibition of the vegetative growth of cereals, resulting in plantswith shorter and sturdy stalks which are not so easily lodged by theaction of wind and rain.

The compounds of the formula I can also be used for defoliating anddesiccating parts of plants above the soil, wherever this is desired.Potato and cotton crops are treated in this manner, e.g. shortly beforeharvesting.

Particularly effective compounds are those of the formula I in which

R₁ is hydrogen or C₁ -C₄ alkyl,

R₂ is C₁ -C₆ alkyl or C₁ -C₄ alkoxy,

R₃ is hydrogen, C₁ -C₄ alkyl, an alkali metal cation or an alkalineearth metal cation or a C₁ -C₄ alkylammonium group the alkyl moieties ofwhich can be substituted by OH, CN or C₁ -C₄ alkoxy,

each of R₄ and R₅ are hydrogen,

each of R₆ and R₇ are hydrogen, C₁ -C₄ alkyl, or one of them is alsophenyl,

each of R₈ and R₉ is hydrogen, C₁ -C₄ alkyl, or one of them is alsophenyl or a C₁ -C₄ alkoxycarbonyl radical,

X₁ and X₂ together are a double bonded oxygen atom, and

Y is oxygen or sulfur.

The best results are obtained with the compounds of formula I in which

R₁ is hydrogen or C₁ -C₄ alkyl,

R₂ is C₁ -C₆ alkyl or methoxy,

R₃ is hydrogen or methyl,

each of R₄ and R₅ is hydrogen,

each of R₆ and R₇ is hydrogen or C₁ -C₄ alkyl,

each of R₈ and R₉ is hydrogen or C₁ -C₄ alkyl,

X₁ and X₂ together are a double bonded oxygen atom, and

Y is oxygen.

In addition to containing the active ingredients of the formula I, thecompositions of this invention contain a suitable carrier and/or otheradjuvants. Suitable carriers and adjuvants can be solid or liquid andcorrespond to the substances customarily employed in the art offormulation, e.g. natural or regenerated mineral substances, solvents,diluents, dispersants, emulsifiers, wetting agents, tackifiers,thickeners, binders and/or fertilisers.

For use in herbicidal compositions, the compounds of the formula I canbe processed to dusts, emulsifiable concentrates, granules, dispersions,or to solutions or suspensions in conventional formulation.

The benzthiazolylurea derivatives of the formula I are obtained bymethods which are known per se, by reacting the appropriatelysubstituted benzthiazolamine or benzthiazole isocyanate with a carbamoylhalide, an isocyanate or an amine.

One process for the production of the benzthiazolylurea derivatives ofthe formula I comprises reacting a benzthiazolamine of the formula II##STR4## wherein R₃ and R₉ and X₁ and X₂ are as defined for formula I,in an inert solvent or diluent and in the presence of an acid acceptor,with a carbamoyl halide of the formula III ##STR5## wherein R₁, R₂ and Yare as defined for formula I.

A process for the production of those benzthiazolylurea derivatives ofthe formula I, wherein R₃ is hydrogen, comprises reacting a benzthiazoleisocyanate or isothiocyanate of the formula IV ##STR6## wherein R₄ to R₉and X₁, X₂ and Y are as defined for formula I, in an inert solvent ordiluent, with an amine of the formula V ##STR7## wherein R₁ and R₂ areas defined for formula I. If desired, the hydrogen atom R₃ can bereplaced by an alkyl group with a suitable alkyl ester in the presenceof a base, or by a basic salt radical with a strong base.

A process for the production of benzthiazolylurea derivatives of theformula I, wherein R₂ is hydrogen, comprises reacting a benzthiazolamineof the formula II, in an inert solvent or diluent, with an isocyanate orisothiocyanate of the formula VI

    R.sub.1 --N═C═Y                                    (VI)

wherein R₁ and Y are as defined for formula I. If desired, the hydrogenatom R₂ can be replaced by an alkyl radical, in the presence of a base,with an appropriate alkyl ester.

These reactions are advantageously conducted in a protic organic solventor diluent, e.g. an alcohol, an ester or ether, a ketone, dimethylformamide, dimethyl sulfoxide or acetonitrile, alone or diluted withwater.

The reaction temperatures are in the range from -10° to +150° C., butare conveniently in the range from room temperature to the boiling pointof the mixture of solvents. The reaction time is from 1 hour to about aday, depending on the starting materials, the solvent and thetemperature.

Where a halogen atom is split off during the reaction, the equimolaramount of an acid acceptor should be used. Suitable acid acceptors are,in principle, all inorganic or organic bases, e.g. NaOH, KOH, NaHCO₃, K₂CO₃ or potassium tert-butylate. However, it is preferred to use asecondary or tertiary amine such as trimethylamine, triethylamine,pyridine, 4-dimethylaminopyridine, potassium tert-butylate, and thelike.

The starting benzthiazolamines of the formula II are obtained byreacting appropriately substituted cyclohexane-1,3-diones withthioureas, in an alkanolic solvent and in the presence of a small amountof iodine as catalyst, e.g. in accordance with the following reactionscheme: ##STR8## Further, the benzthiazolamines of the formula II canalso be obtained by condensing aminonitrile, in the presence of sulfur,to a 3-oxo-4,5-dihydro-6H-aniline in accordance with the reaction scheme##STR9## The diones of the formula VII and the anilines of the formulaVIII can also be cyclised with an aminoisothiocyanate of the formula IX

    R.sub.3 NH--N═C═S                                  (IX)

In the above formulae, R₁ to R₉ are as defined for formula I. Suchcondensation reactions are to be found in Weissenberger, "The Chemistryof Heterocyclic Compounds," Vol. 34, Part 1, p. 213 ff., Part 2, p. 9ff., and in Vol. 39, Part 1, p. 297 ff. (John Wiley+Sons, 1979).Particulars relating to the production of the starting materials orsimilar products are contained in German Offenlegungsschrift No. 1 932699, U.S. Pat. Nos. 3,682,045 and 4,120,690, and in Swiss Pat. No. 528533.

The compounds of the formula I are stable compounds which are soluble incustomary organic solvents such as alcohols, ethers, ketones, dimethylformamide, dimethyl sulfoxide etc. They are not explosive or corrosive,and no special precautionary measures are required for handling them.

The compositions of the present invention are obtained in known mannerby intimately mixing and grinding active ingredients (compounds) of thegeneral formula I with suitable carriers and/or adjuvants, with orwithout the addition of antifoams, wetting agents, dispersants and/orsolvents which are inert to the active ingredients. The activeingredients can be processed to the following formulations:

solid formulations: dust, tracking powders, granules (coated granules,impregnated granules and homogeneous granules),

active ingredient concentrates which are dispersible in water: wettablepowders, pastes, emulsions, emulsifiable concentrates,

liquid formulations: solutions, dispersions.

The concentrations of active ingredient in the compositions of thisinvention are between 1 and 80 percent by weight. As circumstances mayrequire, the active ingredients can also be applied in lowconcentrations of about 0.05 to 1 percent by weight.

The compositions of the present invention can be mixed with otherbiocidal compounds or compositions. Thus in addition to containing thecompounds of the formula I, the compositions of the invention can alsocontain e.g. insecticides, fungicides, bactericides, fungistatic agents,bacteriostatic agents, nematocides or further herbicides, in order tobroaden the activity spectrum.

The following Examples describe in detail the production of a number ofbenzthiazolylurea derivatives of the formula I and compositionscontaining them. Further compounds obtained in similar manner are listedin the table following Example 5. Pressures are in millibars, and partsand percentages are by weight.

EXAMPLE 1N-(5,5-Dimethyl-7-oxo-4,5-dihydro-6H-benzthiazol-2-yl)-N-methylurea##STR10##

(a) 28 g of 2-bromo-5,5-dimethylcyclohexane-1,3-dione and 11.7 g ofthiourea are dissolved in 200 ml of ethanol. After the weakly exothermicreaction has subsided, the mixture is refluxed for a further 6 hours.The solution is diluted with 400 ml of water and neutralised withsaturated sodium bicarbonate solution. The precipitated crystals arecollected by filtration and dried in vacuo at 80° C., affording 21 g of2-amino-5,5-dimethyl-7-oxo-4,5-dihydro-6H-benzthiazole with a meltingpoint of 203°-205° C.

(b) 9 g of the product obtained in (a) and 4 g of methyl isocyanate aredissolved in 150 ml of acetonitrile and the solution is stirredovernight at room temperature. The solution is then concentrated to onethird of its volume and cooled to 0° C. The precipitated crystals arecollected by filtration and dried in vacuo at 80° C., affording 11.5 gof the title compound in the form of colourless crystals with a meltingpoint of 228°-231° C. (compound 1).

EXAMPLE 2N-(5,5-Dimethyl-7-oxo-4,5-dihydro-6H-benzthiazol-2-yl)-N'-methyl-N'-methoxy-urea##STR11## 15 g of 2-amino-5,5-dimethyl-7-oxo-4,5-dihydro-6H-benzthiazoleobtained in Example 1 (a) are dissolved in 100 ml of dimethyl formamideand to this solution are added 8.6 g of potassium tert-butylate. Then11.3 g of methoxymethylcarbamoyl chloride are added dropwise at 0° C.and the reaction mixture is stirred for 3 hours at room temperature. Themixture is then poured into ice/water and extracted with chloroform.Chromatography on silica gel with chloroform/methanol (20:1) as eluantaffords 8 g of the title compound with a melting point of 145°-148° C.(compound 3). EXAMPLE 3N-(5,5-Dimethyl-7-oxo-4,5-dihydro-6H-benzthiazol-2-yl)-N',N'-dimethylurea##STR12## 12 g of 2-amino-5,5-dimethyl-7-oxo-4,5-dihydro-6H-benzthiazole(Example 1 (a), 7.2 g of potassium tert-butylate and 8.6 g ofdimethylcarbamoyl chloride are reacted as described in Example 2,affording 7.6 g of the title compound with a melting point of 175°-180°C. (compound 4). EXAMPLE 4N-Methyl-N-(5,5-dimethyl-7-oxo-4,5-dihydro-6H-benzthiazol-2-yl)-N'-methyl-urea##STR13##

(a) 82 g of 2-bromo-5,5-dimethylcyclohexane-1,3-dione, 40 g of sodiumacetate and 50 g of N-methylthiourea are dissolved in 500 ml of aceticacid. The mixture is stirred at room temperature until the weaklyexothermic reaction has subsided, and then refluxed for 3 hours. Thereaction mixture is then concentrated to one third of its volume in arotary evaporator, poured into 100 ml of water and cooled to 0° C. Theprecipitate is collected by filtration and dried in vacuo at 80° C.,affording 64 g of2-methylamino-5,5-dimethyl-7-oxo-4,5-dihydro-6H-benzthiazole with amelting point of 217°-218° C.

(b) 15 g of the product obtained in (a) and 5 ml of methyl isocyanateare suspended in 100 ml of acetonitrile and stirred overnight at roomtemperature. 1 ml of triethylamine is added as catalyst (in a furtherexperiment, 100 mg of 4-dimethylaminopyridine are added with equalsuccess). The reaction solution is then concentrated in a rotaryevaporator and the residue is crystallised from a mixture ofchloroform/hexane (1:1), affording 14 g of the title compound with amelting point of 174°-175° C. (compound 4).

EXAMPLE 5N-Methyl-N-(5,5-dimethyl-7-oxo-4,5-dihydro-6H-benzthiazol-2-yl)-N'-tert-butyl-urea##STR14## 15 g of2-methylamino-5,5-dimethyl-7-oxo-4,5-dihydro-6H-benzthiazole (obtainedin Example 4 (a) are suspended in 100 ml of acetonitrile. Then 8.2 g oftert-butylisocyanate and 1 g of potassium tert-butylate are added at 0°C. The mixture is subsequently stirred for 24 hours at room temperature.Working up is as described in Example 4 (b), affording 10.8 g of thetitle compound in the form of colourless crystals with a melting pointof 165°-167° C. (compound 5).

Further compounds which are obtained by procedures similar to thosedescribed in the foregoing Examples are listed in the following table:

    __________________________________________________________________________     ##STR15##                                                                                                                          physical                NO. R.sub.8, R.sub.9                                                                      R.sub.6, R.sub.7                                                                        R.sub.4, R.sub.5                                                                      X.sub.1, X.sub.2                                                                    Y  R.sub.3                                                                              NR.sub.1 R.sub.2                                                                      data                    __________________________________________________________________________                                                          (°C.)            1   H.sub.2 (CH.sub.3).sub.2                                                                        H.sub.2 O     O  H      NHCH.sub.3                                                                            m.p.                                                                          228-231°         2   H.sub.2 (CH.sub.3).sub.2                                                                        H.sub.2 O     O  CH.sub.3                                                                             NHCH.sub.3                                                                            m.p.                                                                          174-175°         3   H.sub.2 (CH.sub.3).sub.2                                                                        H.sub.2 O     O  H      N(CH.sub.3)OCH.sub.                                                                   m.p. 145-8°      4   H.sub.2 (CH.sub.3).sub.2                                                                        H.sub.2 O     O  H      N(CH.sub.3).sub.2                                                                     m.p.                                                                          175-180°         5   H.sub.2 (CH.sub.3).sub.2                                                                        H.sub.2 O     O  CH.sub.3                                                                             N(CH.sub.3)OCH.sub.3                                                                  m.p.                                                                          108-110°         6   H.sub.2 (CH.sub.3).sub.2                                                                        H.sub.2 O     O  H      NHC.sub.4 H.sub.9 n                                                                   m.p. 204-6°      7   H.sub.2 (CH.sub.3).sub.2                                                                        H.sub.2 O     O  CH.sub.3                                                                             NHC.sub.4 H.sub.9 n                                                                   m.p. 124-6°      8   H.sub.2 (CH.sub.3).sub.2                                                                        H.sub.2 O     O  CH.sub.3                                                                             NHC.sub.4 H.sub.9                                                                     m.p. 165-7°      9   H.sub.2 (CH.sub.3).sub.2                                                                        H.sub.2 O     O  CH.sub.3                                                                             N(CH.sub.3).sub.2                                                                     m.p. 165-7°      10  H.sub.2 (CH.sub.3).sub.2                                                                        H.sub.2 O     O  Na     N(CH.sub.3).sub.2               11  H.sub.2 (CH.sub.3).sub.2                                                                        H.sub.2 O     O  Na     N(CH.sub.3) OCH.sub.3           12  H.sub.2 (CH.sub.3).sub.2                                                                        H.sub.2 O     S  CH.sub.3                                                                             NHCH.sub.3                                                                            m.p.                                                                          157-60°          13  H.sub.2 (CH.sub.3).sub.2                                                                        H.sub.2 O     O  NH.sub.3 C.sub.3 H.sub.                                                              N(CH.sub.3)OCH.sub.3            14  H.sub.2 (CH.sub.3).sub.2                                                                        H.sub.2 O     O  NH.sub.3 C.sub.3 H.sub.7                                                             N(CH.sub.3) OCH.sub.3           15  H.sub.2 (CH.sub.3).sub.2                                                                        H.sub.2 O     O  NH(CH.sub.3).sub.3                                                                   N(CH.sub.3)OCH.sub.3            16  H.sub.2 (CH.sub.3).sub.2                                                                        H.sub.2 O     O  H                                                                                     ##STR16##                      17  H.sub.2 (CH.sub.3).sub.2                                                                        H.sub.2 O     O  NH(CH.sub.3).sub.3                                                                   N(CH.sub.3).sub.2               18  H.sub.2 (CH.sub.3).sub.2                                                                        H.sub.2 O     O  H                                                                                     ##STR17##                      19  H.sub.2 (CH.sub.3).sub.2                                                                        H.sub.2 O     O  H                                                                                     ##STR18##                      20  H.sub.2 (CH.sub.3).sub.2                                                                        H, COOCH.sub.3                                                                        O     O  CH.sub.3                                                                             NHCH.sub.3                      21  H.sub.2 (CH.sub.3).sub.2                                                                        H, COOCH.sub.3                                                                        O     O  CH.sub.3                                                                             NHC.sub.4 H.sub.9 n             22  H.sub.2 (CH.sub.3 ).sub.2                                                                       H, COOCH.sub.3                                                                        O     O  H      N(CH.sub.3).sub.2               23  H.sub.2 (CH.sub.3).sub.2                                                                        H, COOCH.sub.3                                                                        O     O  H      N(CH.sub.3)OCH.sub.3            24  H.sub.2 (CH.sub.3).sub.2                                                                        H, COOCH.sub.3                                                                        O     S  CH.sub.3                                                                             NHCH.sub.3                      25  H.sub.2 (CH.sub.3).sub.2                                                                        H, CN   O     O  CH.sub.3                                                                             NHCH.sub.3                      26  H.sub.2 (CH.sub.3).sub.2                                                                        H, CN   O     O  CH.sub.3                                                                             N(CH.sub.3)OCH.sub.3            27  H.sub.2 (CH.sub.3).sub.2                                                                        H, CN   O     O  H      N(CH.sub.3).sub.2               28  H.sub.2 (CH.sub.3).sub.2                                                                         ##STR19##                                                                            O     O  CH.sub.3                                                                             NHCH.sub.3                      29  H.sub.2 (CH.sub.3).sub.2                                                                         ##STR20##                                                                            O     O  H      N(CH.sub.3).sub.2               30  H.sub.2 (CH.sub.3).sub.2                                                                         ##STR21##                                                                            O     O  H      N(CH.sub.3)OCH.sub.3            31  H.sub.2 (CH.sub.3).sub.2                                                                        CH.sub.3, COOCH.sub.3                                                                 O     O  CH.sub.3                                                                             NHCH.sub.3                      32  H.sub.2 (CH.sub.3).sub.2                                                                        CH.sub.3, COOCH.sub.3                                                                 O     O  CH.sub.3                                                                             NHC.sub.4 H.sub.9 n             33  H.sub.2 (CH.sub.3).sub.2                                                                        CH.sub.3, COOCH.sub.3                                                                 O     O  H      N(CH.sub.3).sub.2               34  H.sub.2 (CH.sub.3).sub.2                                                                        CH.sub.3, COOCH.sub.3                                                                 O     O  H      N(CH.sub.3)OCH.sub.3            35  H.sub.2 (CH.sub.3).sub.2                                                                        CH.sub.3, COOH                                                                        O     O  CH.sub.3                                                                             NHCH.sub.3                      36  H.sub.2 (CH.sub.3).sub.2                                                                        CH.sub.3, COOH                                                                        O     O  H      N(CH.sub.3).sub.2               37  H.sub.2 (CH.sub.3).sub.2                                                                        CH.sub.3, COOH                                                                        O     O  H      N(CH.sub.3)OCH.sub.3            38  H.sub.2 (CH.sub.3).sub.2                                                                        H, Br   O     O  H      N(CH.sub.3).sub.2               39  H.sub.2 (CH.sub.3).sub.2                                                                        H, Br   O     O  CH.sub.3                                                                             NHCH.sub.3                      40  H.sub.2 (CH.sub.3).sub.2                                                                        H, Br   O     O  H      N(CH.sub.3)OCH.sub.3            41  H.sub.2 (CH.sub.3).sub.2                                                                        H, COOCH.sub.3                                                                        O     O  Na     N(CH.sub.3).sub.2               42  H.sub.2 (CH.sub.3).sub.2                                                                        H, COOCH.sub.3                                                                        O     O  Na     N(CH.sub.3)OCH.sub.3            43  H.sub.2 (CH.sub.3).sub.2                                                                        H, COOCH.sub.3                                                                        O     O  NH.sub.3 C.sub.3 H.sub.7                                                             N(CH.sub.3).sub.2               44  H.sub.2 (CH.sub.3).sub.2                                                                        H, COOCH.sub.3                                                                        O     O  NH.sub.3 C.sub.3 H.sub.7                                                             N(CH.sub.3)OCH.sub.3            45  H.sub.2 (CH.sub.3).sub.2                                                                        H, COOCH.sub.3                                                                        O     O  NH(CH.sub.3).sub.3                                                                   N(CH.sub.3).sub.2               46  H.sub.2 (CH.sub.3).sub.2                                                                        H, COOCH.sub.3                                                                        O     O  NH(CH.sub.3).sub.3                                                                   N(CH.sub.3)OCH.sub.3            47  H.sub.2 (CH.sub.3).sub.2                                                                        H, COOCH.sub.3                                                                        O     O  H                                                                                     ##STR22##                      48  H.sub.2 (CH.sub.3).sub.2                                                                        H, COOCH.sub.3                                                                        O     O  H                                                                                     ##STR23##                      49  H.sub.2 (CH.sub.3).sub.2                                                                        H, COOCH.sub.3                                                                        O     O  H                                                                                     ##STR24##                      50  H.sub.2 (CH.sub.3).sub.2                                                                        H, CONH.sub.2                                                                         O     O  H      N(CH.sub.3).sub.2               51  H.sub.2 (CH.sub.3).sub.2                                                                        H, CONHC.sub.2 H.sub.5                                                                O     O  H      N(CH.sub.3).sub.2               52  H.sub.2 (CH.sub.3).sub.2                                                                        H, COOC.sub.4 H.sub.9 n                                                               O     O  H      N(CH.sub.3).sub.2               53  H, COOCH.sub.3                                                                        (CH.sub.3).sub.2                                                                        H.sub.2 O     O  CH.sub.3                                                                             NHCH.sub.3                                                                            m.p.                                                                          152-154°         54  H, COOCH.sub.3                                                                        (CH.sub.3).sub.2                                                                        H.sub.2 O     O  CH.sub.3                                                                             NHC.sub.4 H.sub.9 n             55  H, COOCH.sub.3                                                                        (CH.sub.3).sub.2                                                                        H.sub.2 O     O  H      N(CH.sub.3).sub.2               56  H, COOCH.sub.3                                                                        (CH.sub.3).sub.2                                                                        H.sub.2 O     O  H      N(CH.sub.3)OCH.sub.3                                                                  m.p. 80-88°      57  H, COOCH.sub.3                                                                        (CH.sub.3).sub.2                                                                        H.sub.2 O     S  CH.sub.3                                                                             NHCH.sub.3                      58  H, CH.sub.3                                                                           (CH.sub.3).sub.2                                                                        H.sub.2 O     O  CH.sub.3                                                                             NHCH.sub.3                                                                            m.p.                                                                          133-136°         59  H, CN   (CH.sub.3).sub.2                                                                        H.sub.2 O     O  H      N(CH.sub.3).sub.2               60  H, CH.sub.3                                                                           (CH.sub.3).sub.2                                                                        H.sub.2 O     O  CH.sub.3                                                                             N(CH.sub.3)OCH.sub.3                                                                  m.p.                                                                          111-118°         61                                                                                 ##STR25##                                                                            (CH.sub.3).sub.2                                                                        H.sub.2 O     O  CH.sub.3                                                                             NHCH.sub.3                      62                                                                                 ##STR26##                                                                            (CH.sub.3).sub.2                                                                        H.sub.2 O     O  H      N(CH.sub.3).sub.2               63                                                                                 ##STR27##                                                                            (CH.sub.3).sub.2                                                                        H.sub.2 O     O  H      N(CH.sub.3).sub.2 OCH.sub.3     64  CH.sub.3, COOCH.sub.3                                                                 (CH.sub.3).sub.2                                                                        H.sub.2 O     O  CH.sub.3                                                                             NHCH.sub.3                                                                            m.p.                                                                          178-179°         65  CH.sub.3, COOCH.sub.3                                                                 (CH.sub.3).sub.2                                                                        H.sub.2 O     O  CH.sub.3                                                                             NHC.sub.4 H.sub.9 N             66  CH.sub.3, COOCH.sub.3                                                                 (CH.sub.3).sub.2                                                                        H.sub.2 O     O  H      N(CH.sub.3).sub.2               67  CH.sub.3, COOCH.sub.3                                                                 (CH.sub.3).sub.2                                                                        H.sub.2 O     O  H      N(CH.sub.3)OCH.sub.3                                                                  m.p.                                                                          100-104°         68  CH.sub.3, COOH                                                                        (CH.sub.3).sub.2                                                                        H.sub.2 O     O  CH.sub.3                                                                             NHCH.sub.3                      69  CH.sub.3, COOH                                                                        (CH.sub.3).sub.2                                                                        H.sub.2 O     O  H      N(CH.sub.3).sub.2               70  CH.sub.3, COOH                                                                        (CH.sub.3).sub.2                                                                        H.sub.2 O     O  H      N(CH.sub.3)OCH.sub.3            71  Br, H   (CH.sub.3).sub.2                                                                        H.sub.2 O     O  H      N(CH.sub.3).sub.2               72  Br, H   (CH.sub.3).sub.2                                                                        H.sub.2 O     O  CH.sub.3                                                                             NHCH.sub.3                      73  Br, H   (CH.sub.3).sub.2                                                                        H.sub.2 O     O  H      N(CH.sub.3)OCH.sub.3            74  H, COOCH.sub.3                                                                        (CH.sub.3).sub.2                                                                        H.sub.2 O     O  Na     N(CH.sub.3).sub.2               75  H, COOCH.sub.3                                                                        (CH.sub.3).sub.2                                                                        H.sub.2 O     O  Na     N(CH.sub.3)OCH.sub.3            76  H, COOCH.sub.3                                                                        (CH.sub.3).sub.2                                                                        H.sub.2 O     O  NH.sub.3 C.sub.3 H.sub.7                                                             N(CH.sub.3).sub.2               77  H, COOCH.sub.3                                                                        (CH.sub.3).sub.2                                                                        H.sub.2 O     O  NH.sub.3 C.sub.3 H.sub.7                                                             N(CH.sub.3)OCH.sub.3            78  H, COOCH.sub.3                                                                        (CH.sub.3).sub.2                                                                        H.sub.2 O     O  NH(CH.sub.3).sub.3                                                                   N(CH.sub.3).sub.2               79  H.sub.2 C.sub.3 H.sub.7 iso, H                                                                  H.sub.2 O     O  CH.sub.3                                                                             N(CH.sub.3)OCH.sub.3                                                                  m.p.                                                                          106-107°         80  H, COOCH.sub.3                                                                        (CH.sub. 3).sub.2                                                                       H.sub.2 O     O  H                                                                                     ##STR28##                      81  H.sub.2 COOCH.sub.3                                                                   (CH.sub.3).sub.2                                                                        H.sub.2 O     O  H                                                                                     ##STR29##                      82  H, COOCH.sub.3                                                                        (CH.sub.3).sub.2                                                                        H.sub.2 O     O  H                                                                                     ##STR30##                      83  H       C.sub.4 H.sub.9 (t), H                                                                  H.sub.2 O     O  CH.sub.3                                                                             NHC.sub.4 H.sub.9 n                                                                   m.p.                                                                          125-129°         84  H, CH.sub.3                                                                           (CH.sub.3).sub.2                                                                        H.sub.2 O     O  CH.sub.3                                                                             NHC.sub.4 H.sub.9 n                                                                   m.p. 92-95°      85  H.sub.2 (CH.sub.3).sub.2                                                                        H.sub.2 O     O  CH.sub.3                                                                             NHC.sub.2 H.sub.5                                                                     m.p.                                                                          144-145°         86  H.sub.2 H.sub.2   H.sub.2 O     O  H      N(CH.sub.3).sub.2                                                                     m.p.                                                                          178-181°         87  H.sub.2 H.sub.2   H.sub.2 O     O  H      NHCH.sub.3                                                                            m.p.                                                                          225-228°         88  H.sub.2 H.sub.2   H.sub.2 O     O  H      N(CH.sub.3)OCH.sub.3                                                                  m.p.                                                                          165-167°         89  H.sub.2 H.sub.2   H.sub.2 O     O  CH.sub.3                                                                             NHCH.sub.3                      90  H.sub.2 H.sub.2                                                                                  ##STR31##                                                                            O     O  H      N(CH.sub.3).sub.2               91  H.sub.2 H.sub.2                                                                                  ##STR32##                                                                            O     O  H      N(CH.sub.3)OCH.sub.3            92  H.sub.2                                                                                          ##STR33##                                                                            O     O  CH.sub.3                                                                             NHCH.sub.3                      93                                                                                 ##STR34##                                                                            H.sub.2   H.sub.2 O     O  H      N(CH.sub.3).sub.2               94                                                                                 ##STR35##                                                                            H.sub.2   H.sub.2 O     O  H      N(CH.sub.3)OCH.sub.3            95                                                                                 ##STR36##                                                                            H.sub. 2  H.sub.2 O     O  CH.sub.3                                                                             NHCH.sub.3                      96  H.sub.2                                                                                ##STR37##                                                                              H.sub.2 O     O  H      N(CH.sub.3).sub.2               97  H.sub.2                                                                                ##STR38##                                                                              H.sub.2 O     O  H      N(CH.sub.3)OCH.sub.3            98  H.sub.2                                                                                ##STR39##                                                                              H.sub.2 O     O  CH.sub.3                                                                             NHCH.sub.3                                                                            m.p.                                                                          170-175°         99  H.sub.2                                                                                ##STR40##                                                                              H, COOCH.sub.3                                                                        O     O  H      N(CH.sub.3).sub.2               100 H.sub.2                                                                                ##STR41##                                                                              H, COOCH.sub.3                                                                        O     O  H      N(CH.sub.3)OCH.sub.3            101 H.sub.2                                                                                ##STR42##                                                                              H, COOCH.sub.3                                                                        O     O  CH.sub.3                                                                             NHCH.sub.3                      102 H, COOCH.sub.3                                                                         ##STR43##                                                                              H.sub.2 O     O  H      N(CH.sub.3).sub.2                                                                     m.p.                                                                          140-150°         103 H, COOCH.sub.3                                                                         ##STR44##                                                                              H.sub.2 O     O  H      N(CH.sub.3)OCH.sub.3                                                                  m.p. 80°         104 H, COOCH.sub.3                                                                         ##STR45##                                                                              H.sub.2 O     O  CH.sub.3                                                                             NHCH.sub.3                                                                            m.p.                                                                          173-175° C.      105 H.sub.2 H, C.sub.3 H.sub.7 iso                                                                  H.sub.2 O     O  H      N(CH.sub.3).sub.2               106 H.sub.2 H, C.sub.3 H.sub.7 iso                                                                  H.sub.2 O     O  H      N(CH.sub.3)OCH.sub.3            107 H.sub.2 H, C.sub.3 H.sub.7 iso                                                                  H.sub.2 O     O  CH.sub.3                                                                             NHCH.sub.3                                                                            m.p.                                                                          134-136°         108 H.sub.2 H, C.sub.3 H.sub.7 iso                                                                  H, COOCH.sub.3                                                                        O     O  H      N(CH.sub.3).sub.2               109 H.sub.2 H, C.sub.3 H.sub.7 iso                                                                  H, COOCH.sub.3                                                                        O     O  H      N(CH.sub.3)OCH.sub.3            110 H.sub.2 H, C.sub.3 H.sub.7 iso                                                                  H, COOCH.sub.3                                                                        O     O  CH.sub.3                                                                             NHCH.sub.3                      111 H, COOCH.sub.3                                                                        H, C.sub.3 H.sub.7 iso                                                                  H.sub.2 O     O  H      N(CH.sub.3).sub.2               112 H, COOCH.sub.3                                                                        H, C.sub.3 H.sub.7 iso                                                                  H.sub.2 O     O  H      N(CH.sub.3)OCH.sub.3                                                                  m.p.                                                                          185-190°         113 H, COOCH.sub.3                                                                        H, C.sub.3 H.sub.7 iso                                                                  H.sub.2 O     O  CH.sub.3                                                                             NHCH.sub.3                                                                            m.p.                                                                          130-135°         114 H.sub.2 H, C.sub.4 H.sub.9 t                                                                    H.sub.2 O     O  H      N(CH.sub.3).sub.2               115 H.sub.2 H, C.sub.4 H.sub.9 t                                                                    H.sub.2 O     O  H      N(CH.sub.3)OCH.sub.3                                                                  m.p. 95°         116 H.sub.2 H, C.sub.4 H.sub.9 t                                                                    H.sub.2 O     O  CH.sub.3                                                                             NHCH.sub.3                                                                            m.p.                                                                          150-152°         117 H.sub.2 H, C.sub.4 H.sub.9 t                                                                    H, COOCH.sub.3                                                                        O     O  H      N(CH.sub.3).sub.2               118 H.sub.2 H, C.sub.4 H.sub.9 t                                                                    H, COOCH.sub.3                                                                        O     O  H      N(CH.sub.3 OCH.sub.3            119 H.sub.2 H, C.sub.4 H.sub.9 t                                                                    H, COOCH.sub.3                                                                        O     O  CH.sub.3                                                                             NHCH.sub.3                      120 H, COOCH.sub.3                                                                        H, C.sub.4 H.sub.9 t                                                                    H.sub.2 O     O  H      N(CH.sub.3).sub.2               121 H, COOCH.sub.3                                                                        H, C.sub.4 H.sub.9 t                                                                    H.sub.2 O     O  H      N(CH.sub.3)OCH.sub.3            122 H, COOCH.sub.3                                                                        H, C.sub.4 H.sub.9 t                                                                    H.sub.2 O     O  CH.sub.3                                                                             NHCH.sub.3                      123 H.sub.2                                                                                ##STR46##                                                                              H.sub.2 O     O  CH.sub.3                                                                             NHCH.sub.3                      124 H.sub.2                                                                                ##STR47##                                                                               ##STR48##                                                                            O     O  H      N(CH.sub.3).sub.2               125 H.sub.2 H, CHCHCH.sub.3                                                                         H.sub.2 O     O  CH.sub.3                                                                             NHCH.sub.3                      126 H.sub.2                                                                                ##STR49##                                                                              H.sub.2 O     O  CH.sub.3                                                                             NHCH.sub.3                      127                                                                                ##STR50##                                                                             ##STR51##                                                                              H.sub.2 O     O  CH.sub.3                                                                             NHCH.sub.3                      128 H,    (CH.sub.2).sub.4                                                                   H      H.sub.2 O     O  CH.sub.3                                                                             NHCH.sub.3                      129 H     (CH.sub.2).sub.4                                                                   H      H.sub.2 O     O  CH.sub.3                                                                             NHCH.sub.3                      130 H.sub.2 (CH.sub.3).sub.2                                                                        H.sub.2 O(CH.sub.2).sub.2 O                                                                 O  CH.sub.3                                                                             NHCH.sub.3                      131 H.sub.2 (CH.sub.3).sub.2                                                                        H.sub.2 S(CH.sub.2).sub.2 S                                                                 O  CH.sub.3                                                                             NHCH.sub.3                      132 H.sub.2 (CH.sub.3).sub.2                                                                        H.sub.2 O(CH.sub.2).sub.2 O                                                                 O  H      N(CH.sub.3).sub.2               133 H.sub.2 (CH.sub.3).sub.2                                                                        H, COOCH.sub.3                                                                        O(CH.sub.2).sub.2 O                                                                 O  H      N(CH.sub.3).sub.2               134 H.sub.2 H.sub.2   H.sub.2 O(CH.sub.2).sub.2 O                                                                 O  CH.sub.3                                                                             NHCH.sub.3                      135 H, COOCH.sub.3                                                                        (CH.sub.3).sub.2                                                                        H.sub.2 O(CH.sub.2).sub.2 O                                                                 O  CH.sub.3                                                                             NHCH.sub.3                      136 H.sub.2 H, C.sub.3 H.sub.7  iso                                                                 CH.sub.3 COOCH.sub.3                                                                  O(CH.sub.2).sub.2 O                                                                 O  H      N(CH.sub.3)OCH.sub.3            137 H, CH.sub.3                                                                           H, C.sub.3 H.sub.7 (i)                                                                  H       O     O  CH.sub.3                                                                             N(CH.sub.3).sub.2               138 H, CH.sub.3                                                                           H, C.sub.3 H.sub.7 (i)                                                                  H.sub.2 O     O  CH.sub.3                                                                             NHCH.sub.3                      139 H, C.sub.2 H.sub.5                                                                    H, C.sub.3 H.sub.7 (i)                                                                  H.sub.2 O     O  CH.sub.3                                                                             NHC.sub.4 H.sub.9 (n)           140 H, C.sub.2 H.sub.5                                                                    (CH.sub.3).sub.2                                                                        H.sub.2 O     O  CH.sub.3                                                                             N(CH.sub.3).sub.2               141 H C.sub.2 H.sub.5                                                                     (CH.sub.3).sub.2                                                                        H.sub.2 O     O  CH.sub.3                                                                             NHCH.sub.3                      142 H C.sub.2 H.sub.5                                                                     C.sub.3 H.sub.7 (i), H                                                                  H.sub.2 O     O  H      N(CH.sub.3)OCH.sub.3            143 H C.sub.3 H.sub.7 n                                                                   (CH.sub.3).sub.2                                                                        H.sub.2 O     O  CH.sub.3                                                                             NHCH.sub.3                      144 H C.sub.3 H.sub.7 n                                                                   (CH.sub.3).sub.2                                                                        H.sub.2 O     O  H      N(CH.sub.3).sub.2               145 H C.sub.4 H.sub.9 n                                                                   (CH.sub.3).sub.2                                                                        H.sub.2 O     O  CH.sub.3                                                                             NHCH.sub.3                      146 H C.sub.4 H.sub. 9 n                                                                  (CH.sub.3).sub.2                                                                        H.sub.2 O     O  H      N(CH.sub.3)OCH.sub.3            __________________________________________________________________________

EXAMPLE 6

The compounds of formula I can be formulated to herbicidal compositionse.g. by one of the following procedures.

Granules

The following substances are used to formulate 5% granules:

5 parts ofN-(5,5-dimethyl-7-oxo-4,5-dihydro-6H-benzthiazol-2-yl)-N'-methyl-urea,

0.25 part of epichlorohydrin,

0.25 part of cetyl polyglycol ether,

3.50 parts of polyethylene glycol,

91 parts of kaolin (particle size 0.3-0.8 mm).

The active ingredient is mixed with epichlorohydrin and the mixture isdissolved in 6 parts of acetone; the polyethylene glycol and cetylpolyglycol ether are then added. The resultant solution is sprayed onkaolin, and the acetone is subsequently evaporated in vacuo.

Wettable Powder

The following constituents are used to formulate (a) a 70% and (b) a 10%wettable powder:

(a)

70 parts ofN-(5,5-dimethyl-7-oxo-4,5-dihydro-6H-benzthiazol-2-yl)-N'-methyl-N'-methoxy-urea,

5 parts of sodium dibutylnaphthylsulfonate,

3 parts of naphthalenesulfonic acid/phenolsulfonic acid/formaldehydecondensate (3:2:1),

10 parts of kaolin,

12 parts of Champagne chalk;

(b)

10 parts of the above compound,

3 parts of a mixture of the sodium salts of saturated fatty alcoholsulfates,

5 parts of naphthalenesulfonic acid/formaldehyde condensate,

83 parts of kaolin.

The active ingredient is applied to the corresponding carriers (kaolinand chalk) and then these are mixed and ground, to yield wettablepowders of excellent wettability and suspension power. By diluting thesewettable powders with water it is possible to obtain suspensionscontaining 0.1 to 8% of active ingredient. These suspensions aresuitable for controlling weeds in cultivations of plants.

Paste

The following substances are used to formulate a 45% paste:

45 parts ofN-(5,5-dimethyl-7-oxo-4,5-dihydro-6H-benzthiazol-2-yl)-N',N'-dimethylurea,

5 parts of sodium aluminum silicate,

14 parts of cetyl polyglycol ether with 8 moles of ethylene oxide,

1 part of oleyl polyglycol ether with 5 moles of ethylene oxide,

2 parts of spindle oil,

10 parts of polyethylene glycol,

23 parts of water.

The active ingredient is intimately mixed with the adjuvants inappropriate devices and ground. By diluting the resultant paste withwater, it is possible to prepare suspensions of the desiredconcentration.

Emulsifiable Concentrate

The following ingredients are mixed to formulate a 25% emulsifiableconcentrate:

25 parts ofN-methyl-N-(5,5-dimethyl-7-oxo-4,5-dihydro-6H-benzthiazol-2-yl)-N'-methylurea,

5 parts of a mixture of nonylphenolpolyoxyethylene and calciumdodecylbenzenesulfonate,

15 parts of cyclohexanone,

55 parts of xylene.

This concentrate can be diluted with water to give emulsions in suitableconcentrations.

EXAMPLE 7

The following test methods were employed to determine the herbicidal andplant growth-inhibiting action of the compounds of formula I.

Preemergence herbicidal action

In a greenhouse, plant seeds are sown in flower pots of 12-15 cm indiameter such that 12-25 plants are able to develop in each pot.Directly after sowing, the surface of the soil is treated with anaqueous suspension of the active ingredients, obtained from a 10%wettable powder. Four different concentration series are employed,corresponding to rates of application of 4, 2, 1 and 0.5 kg of activeingredient per hectare respectively. The pots are then kept in thegreenhouse at 22°-25° C. and 50-70% relative humidity. The test isevaluated after 3 weeks and the state of the plants is assessed inaccordance with the following rating:

9=normal growth, as untreated controls

8-2=increasing stages of damage

1=plant withered

The results are reported in the following table.

    ______________________________________                                                     Compound                                                                      2      3     4        9   58                                                  Rate of application in kg/ha:                                    Plants:        4 2      4 2   4 2    4 2 4 2                                  ______________________________________                                        Avena fatua    1 1      1 2   1 1    1 1 1 1                                  Bromus tectorum                                                                              1 1      2 3   1 2    1 1 1 1                                  Lolium perenne 1 1      2 2   2 3    1 1 1 2                                  Alopecurus myos.                                                                             1 1      2 2   2 2    1 1 1 1                                  Sorghum halepense                                                                            1 1      1 1   1 1    1 1 1 2                                  Abutilon       1 1      1 1   1 1    1 1 1 1                                  Sida spinosa   1 1      1 1   1 2    1 1 1 1                                  Amaranthus retrofl.                                                                          1 1      1 1   1 1    1 1 1 1                                  Solanum nirgrum                                                                              1 1      1 1   1 1    1 1 1 1                                  Ipomoea purpurea                                                                             1 1      1 1   1 1    1 1 1 1                                  Sinapis alba   1 1      1 1   1 1    1 1 1 1                                  Stellaria media                                                                              1 1      1 1   1 1    1 1 1 1                                  Chrysanthemum leuc.                                                                          1 1      1 1   1 1    1 1 1 1                                  ______________________________________                                    

Postemergence herbicidal action

Different cultivated plants and weeds are reared from seeds in pots in agreenhouse until they have reached the 4-6 leaf stage. The plants arethen sprayed with aqueous emulsions (obtained from a 5% emulsifiableconcentrate) at different rates of application. The treated plants arethen kept under optimum conditions of light, regular watering, 22°-25°C. and 50-70% relative humidity. The test is evaluated 15 days aftertreatment. The state of the plants is assessed in accordance with thesame rating as employed for the preemergence test, and the results arereported in the following table.

    ______________________________________                                                   Compound                                                                      2   3        4     5     9   58                                               Rate of application in kg/ha:                                      Plants:      4 2   4 2      4 2 4 2   4 2 4 2                                 ______________________________________                                        Avena fatua  1 1   1 2      2 2 1 2   1 1 1 2                                 Lolium perenne                                                                             1 1   1 2      4 7 2 2   1 1 1 4                                 Alopecurus myos                                                                            1 1   1 2      2 2 2 3   1 1 1 2                                 uroides                                                                       Digitaria    1 1   2 2      1 1 1 2   1 1 3 4                                 sangiunalis                                                                   Echinochloa  1 1   2 3      2 2 2 4   1 2 1 2                                 crus galli                                                                    Abutilon     1 1   1 1      1 1 1 1   1 1 1 1                                 Sida spinosa 1 1   1 1      1 1 1 1   1 1 1 1                                 Amaranthus   1 1   1 1      1 1 1 1   1 1 1 1                                 retrofl.                                                                      Solanum nigrum                                                                             1 1   1 1      1 1 1 1   1 1 1 1                                 Ipomea purpurea                                                                            1 1   1 1      1 1 1 1   1 1 1 1                                 Sinapis alba 1 1   1 1      1 1 1 1   1 1 1 1                                 Stellaria media                                                                            1 1   1 1      1 1 1 1   1 1 1 1                                 Chrysanthemum                                                                              1 1   1 1      1 1 1 1   1 1 1 1                                 leuc.                                                                         Galium aparine                                                                             1 1   1 1      1 1 1 1   1 1 1 1                                 Sesbania exaltata                                                                          1 1   1 1      1 1 1 1   1 1 1 1                                 ______________________________________                                    

Growth regulation and yield increase in soybeans

Soybeans of the "Hark" variety are sown in plastic containers in anearth/turf/sand mixture (6:3:1) in a climatic chamber in a greenhouse.By means of an optimum control of temperature, watering and lighting, aswell as by addition of fertiliser, plants in the 5-6 trefoil leaf stagewere able to develop after about 5 weeks. At this time the plants aresprayed with aqueous mixtures of an active ingredient in concentrationsof 10, 50, 100 and 500 ppm until they are dripping wet. The plants arethen further reared until the test is evaluated 5 weeks after treatment.Compared with untreated controls, 10 soybean plants treated withcompound 83 at rates of application of 50 and 100 ppm exhibited thefollowing features:

a respective increase in weight of the harvested siliques of 13 and 17%,

a reduction of the growth in height of 9 and 14% respectively,

an average growth of sucker formation of 5-11%.

Desiccation and defoliation action

Cotton plants of the variety Deltapine are reared in earthenware pots ina greenhouse. After the first capsules have formed, the plants aresprayed with aqueous compositions of compound 1 at a rate of applicationcorresponding to 1, 2, 0.6 and 0.3 kg/ha respectively in fieldapplication. Untreated plants act as controls. Evaluation of the test ismade 3, 7 and 14 days after application of the active ingredient bydetermining the degree of defoliation (percentage of fallen leaves) andof desiccation (drying out of the leaves remaining on the plant). Plantstreated with compounds 9, 58, 60 and 86 at rates of application of 1.2and 0.6 kg/ha are left after 2 weeks with only a few dried out leaves.

What is claimed is:
 1. A benzthiazolylurea of the formula ##STR52##wherein R₁ is hydrogen or C₁ -C₄ alkyl,R₂ is C₁ -C₆ alkyl or methoxy,orR₁ and R₂ together with the nitrogen atom to which they are attachedform a piperidino or pyrrolidino group which can be substituted by C₁-C₃ alkyl, and each of R₆, R₇, R₈ and R₉ is hydrogen or non-stericallyhindering C₁ -C₄ alkyl.
 2. A benzthiazolylurea according to claim 1wherein R₁ is hydrogen or C₁ -C₄ alkyl, and R₂ is C₁ -C₆ alkyl ormethoxy. 3.N-Methyl-N-(5,5-dimethyl-7-oxo-4,5-dihydro-6H-benzthiazol-2-yl)-N',N'-dimethylurea,according to claim
 2. 4.N-Methyl-N-(5,5-dimethyl-7-oxo-4,5-dihydro-6H-benzthiazol-2-yl)-N'-methyl-N'-methoxy-urea,according to claim
 2. 5.N-Methyl-N-(5,5-dimethyl-7-oxo-4,5-dihydro-6H-benzthiazol-2-yl)-N',N'-dimethylurea,according to claim
 2. 6.N-Methyl-N-(5,5-dimethyl-7-oxo-4,5-dihydro-6H-benzthiazol-2-yl)-N'-methyl-N'-methoxy-urea,according to claim
 2. 7.N-Methyl-N-(5,5-dimethyl-7-oxo-4,5-dihydro-6H-benzthiazol-2-yl)-N'-methylurea,according to claim
 2. 8.N-Methyl-N-(5,5,6-trimethyl-7-oxo-4,5-dihydro-6H-benzthiazol-2-yl)-N'-methylurea,according to claim
 2. 9.N-Methyl-N-(5-tert-butyl-7-oxo-4,5-dihydro-6H-benzthiazol-2-yl)-N'-n-butyl-urea,according to claim
 2. 10.N-Methyl-N-(5,5,6-trimethyl-7-oxo-4,5-dihydro-6H-benzthiazol-2-yl)-N'-methyl-N'-methoxy-urea,according to claim 2.